Atlanta, Georgia (CNN) -- Forecasters are warning that the melt from Friday's rare snowfall across much of the South could freeze overnight Saturday, creating dangerous conditions.

"Be prepared for more black ice in the morning," CNN meteorologist Bonnie Schneider said in a warning to drivers.

The National Weather Service said light snow mixed with sleet will resume Sunday in parts of the South, making roads slick.

Much of the South was still under a winter storm watch, according to the National Weather Service. "Roads will become snow-covered and slippery Sunday night through Monday morning," the weather service said.

One to 3 inches of snow was expected Sunday night into Monday morning in Tennessee and across the mid-South.

Southerners who dared to venture outside Saturday carefully inched their way along icy streets and sidewalks after major snowstorm came calling Friday.

Snow that fell on the relatively warm streets and highways turned instantly to slush and then to ice as temperatures fell after sundown, a National Weather Service statement explained.

A cold front will move in Sunday across much of the South, CNN meteorologist Jacqui Jeras said Saturday.

"For the most part, this is going to be a rain event, a lot less moisture, a lot weaker system," she said. "Then tonight [Saturday] our temperatures drop down below freezing, then we get black ice."

"Road conditions continue to be treacherous," the weather service said in a bulletin Saturday. "Residents are urged to stay off the roads unless there is an emergency."

Ice prompted transportation officials to close roads in Alabama and Georgia, and motorists in Mississippi were warned that freezing fog was making bridges hazardous Saturday morning.

The snow and ice prompted churches and synagogues to cancel Saturday services and colleges to cancel classes and exams. MARTA, the public transit system in Atlanta, Georgia, suspended all bus service until further notice, but trains were running Saturday.

The storm system crawled across from Texas to the Atlantic Coast from before dawn Thursday until 9 a.m. Saturday. During that period, 8.8 inches of snow fell on Harkers Island, North Carolina, according to weather service data. Other notable snowfall totals include: 14.9 inches in Duncanville, Texas; 6 inches in Belleville, Alabama; 6.1 inches in Shreveport, Louisiana; 8 inches in DeKalb, Mississippi; and 7.3 inches in Columbia, South Carolina.

Children hopped up and down with delight as snow fell on Mobile, Alabama, on the usually balmy Gulf Coast.